Among exploration devices which are used in deep seas exploration activity, there is an exploration device which stores the exploration device in a container of a pressure-resistant container, and is used in deep seas of 1000 m or deeper below sea level, for example. As a pressure-resistant container for storing the exploration device, in Patent Literature 1, a pressure-resistant container which includes a body portion which is a tube-shaped first outer shell member that has flange portions on outer circumferential sides of both end portions, and panel board portions which are hemispherical second outer shell members that are disposed at both ends of the body portion and have a flange portion on an outer circumferential side of an opening portion, in which the flange portions of the body portion and the panel board portion abut against each other to combine the flange portions by a bolt and a nut, and which is made of metal such as a titanium alloy, is suggested. In addition, in the pressure-resistant container, ceramic may be used instead of metal.